During the past years, the interest in mobile devices that are functioning not only as phones capable to provide services for voice, video and data but also as camera, radio, etc. has increased. These new capabilities of the phones or other mobile devices require that various voltages are supplied to the various modules that provide the above noted supplemental capabilities, i.e., a first voltage for the camera, a second voltage for the radio, a third voltage for some elements of the phone, etc. However, the power used by these modules becomes significant, even when the functions of the modules are not performed. Because most of the mobile devices draw their power from a battery that has a limited capacity and size, the power used by any additional module in the mobile device should be monitored and reduced to a minimum to allow the mobile device to perform other functions for as long as possible.
Thus, to conserve power and extend a standby time between battery recharges, the mobile devices have their processors configured to shut down or place in a sleeping mode various radio interface related components (e.g., power amplifiers, oscillators, and so on) in order to conserve the battery power. These components are associated with the radio interface of the mobile device. The existing techniques require that the processor, which is part of the mobile device, communicates with these various components of the radio interface and other parts of the mobile device before shutting down the various components. This communication generates an increased processor traffic, which might slow down the mobile device and also may increase the power consumption, which is undesirable.
According to existing mobile devices, extended processor communication is generated for placing regulators into a sleep mode and/or to wake the regulators up from the sleep mode. The regulators are those parts that generate accurate voltage levels to the different components of the mobile platform. Generally, a regulator may include control units and power supply units. Because the battery voltage varies dependent on the capacity left in the battery, the components within the mobile platform need voltage levels that are accurate with only a minor variation of the voltage level irrespective of the battery capacity and load. Thus, the regulators are designed to provide this accurate voltage level to the various components of the mobile device irrespective of the status of the battery. Examples of regulators are known to those skilled in the art and one such example is shown in FIG. 1.
However, even these regulators are using electric power, thus draining the battery when no functions are performed. In this regard, FIG. 1 shows how a set of low drop-out (LDO) regulators 10 is implemented in existing mobile platforms. A battery 11 is the power supply to the Application Specific Integrated Circuit (ASIC), which is not shown in the figure. The battery voltage (BV) is regulated by various LDO regulators 12 to the desired voltage levels with very low drop out voltage over load. Each LDO regulator 12 constitutes the power supply unit for one or more components of the mobile platform, for example, processors (P1) and (P2), an oscillator (O), amplifiers (A1) and (A2), etc., as shown in FIG. 1. As noted above, these components of the mobile platform are related to the radio part of the mobile device. As the mobile device may sporadically communicate information with a serving base station, various components of the radio interface may be entered into a sleep mode to reduce the power consumption. The mobile device monitors, based on some core components that are not entering into the sleep mode, a page channel for example, and reactivates the components entered into the sleep mode when a communication is initiated between the mobile device and the serving base station. As previously discussed, the configuration shown in FIG. 1 requires extended communication between the core components (processor) and the non-core components for deciding which non-core components are to be suspended.
All these radio elements may use different voltages and therefore, they may also need different LDOs in the platform. Software control for the LDOs 12 is achieved by using an interface 14. Registers (not shown) within the ASIC (conventionally more than one register for each LDO) enable/disable different actions for the LDO 12 and the registers are written or read through the interface 14. Several interface writings are needed to control all the regulators 12 going from/to the sleep mode.
Signals DATA and CLOCK are signals needed to communicate through the interface 14 and signals A and B are sleep signals generated by the main processor of the mobile platform when the processor requests that parts of the system should enter to or exit out the sleep mode. The Sleep A and Sleep B signals shown in FIG. 1 are received at a sleep control (SC) unit 16 and based on these signals, the various LDOs 12 are entered into the sleep mode.
Thus, the communications of the main processor with the interface 14 and other components of the device 10 take not only processor time but also battery power. Accordingly, it would be desirable to provide devices, systems and methods that avoid the afore-described problems and drawbacks.